Oxygen Utility Test

The fourth test was to discover if Sarcina lutea was either aerobic (needs oxygen to survive), anaerobic (survives without any oxygen), or facultative (can survive with or without oxygen). To find the results we placed our bacteria in a pickle jar that allowed no air in or out. After a day of growing, Sarcina lutea had made no progress, which suggests that it was an aerobic bacteria.

Antibiotic Sensitivity
Our final procedure was to test different types of antibiotics on our bacteria. To accomplish this, it was necessary to perform a test that is called the Bauer-Kirby test. We spread Petri dishes with our bacteria and we placed four different antibiotics of our choice on four separate quadrants of the Petri dishes. I chose chloramphenicol, ampicillin, streptomycin, and hand sanitizer. After 24 hours of incubation, we measured the diameter of each of the zones of inhibition to see how effective the antibiotics were. Chloramphenicol was in first with a diameter of 40 millimeters, ampicillin was in second with a diameter of 36 millimeters, streptomycin was in third with a diameter of 31 millimeters, and hand sanitizer was in last with a diameter of 16 millimeters.